1. Field of the Invention
The invention relates to a welding torch, in particular a handheld welding torch, for a melting welding wire, which is guided in a wire core arranged within a protective hose, wherein the protective hose and the welding core are fastened within a torch housing of the welding torch independently from one another.
2. Description of the Related Art
A welding torch is usually connected to a welding device by a hose package. The length of the hose package depends on the application and/or the welding torch. When using a push-pull welding torch, the length may be in the range of up to 16 meters. When using a welding torch without a drive unit for the welding wire, the length usually is in the range of 4 meters. The robot torch in robot applications is also connected to the welding device by a hose package. In the hose package, shielding gas, current, cooling media and the like may be conveyed in addition to the welding wire. The welding wire is conveyed in a wire core, and the wire core may be arranged within a protective hose, so the wire core may be replaced as well. In the welding torch, the welding wire leaves the wire core and is transferred to either a contact tube or the drive unit. The transfer of the welding wire is particularly relevant during insertion of the welding wire, to prevent the welding wire from choosing a different path because of its cast (i. e. the diameter of freely lying wire loops on an even surface).
In general, fixing the protective hose is known for welding torches with as well as without drive unit from the prior art, with the wire core being moved in either as far as it will go in the region of the contact tube or up to the wire inlet nozzle.
Welding torches for a melting welding wire of the present type are described in AT 509 589 A4 and WO 2005/021199 A1, for example, wherein the wire core and the protective hose are fastened within the torch housing independently from one another.
A disadvantage here is that this is a fixed and/or rigid fastening of the protective hose. As a consequence, every movement of the welding torch requires overcoming the resistance of the protective hose and the wire core. Since the protective hose is designed relatively stable, a correspondingly high force is required, which has a negative impact on the handling of the welding torch. Together with the weight of the hose package, this required use of force for overcoming the rigidity of the supply lines constitutes an additional burden for the welder.
Another disadvantage for the conveying of the welding wire is present if the wire core is not fixed, so its position may change. For example, the wire core retracts into the protective hose when the hose package is rolled in, thus making it possible for the welding wire to choose a different path in the welding torch during transfer. Accordingly, the insertion process is delayed and might have to be repeated.